1. Field of the Invention
The present invention relates to a beam scanning apparatus for use with laser beam printers or the like.
2. Description of the Related Art
A beam scanning apparatus for use with laser beam printers or the like are adapted in such a way that a light beam issuing from a light source such as a semiconductor laser is collimated with a collimator lens, then deflected for scanning with a rotating polygonal mirror and passed through an imaging lens to form a focused beam spot on an imaging plane.
Besides the need to use the expensive imaging lens and polygonal mirror, the conventional beam scanning apparatus suffers from the problem that the diameter of the imaging lens is as large as about 100 mm and that the size of the polygonal mirror is about 20 mm in terms of the radius of the inscribed circle. Thus, the conventional beam scanning apparatus is unavoidably bulky in size.